SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b03816ed0483aaba5001867bb3053efceebb3f308791bee05a9de78e415acf09' 
  AND token = 'opE8rXQoFKBAhut92H8Wwsq6LKqWKc7r777YcGw9jeA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}